Facile C≡O Triple Bond Cleavage of Carbon Monoxide by a Mononuclear Uranium Borohydride Complex
Yafei Li1, Tianze Xu1, Thayalan Rajeshkumar2
1State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
Abstract:
Complete scission of the C≡O triple bond in carbon monoxide by an actinide complex has so far been restricted to multimetallic nitride-bridged systems, where the reaction proceeds via formation of strong C─N multiple bonds. Here we report an alternative mode of complete CO cleavage mediated by a mononuclear uranium(IV) borohydride complex supported by a double layer N-P ligand at room temperature. Single-crystal x-ray diffraction reveals that the oxygen atom becomes bonded to both uranium and boron (U-O-B), while the carbon atom is inserted into a new hydrocarbyl framework, forming U─C, C─C, and C─Si bonds. Computational studies elucidate a cooperative mechanism involving CO insertion into the U-H-B linkage followed by low-barrier rearrangements. This work demonstrates complete CO cleavage by a mononuclear actinide complex operating through a U-H-B cooperative pathway, thereby establishing an alternative, nitride-free route for this transformation at a single uranium center.
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